The present invention relates to a multi-layered filter apparatus. More particularly, the present invention relates to a multi-layered filter apparatus wherein various ones of the layers are individually removable so as to provide a filter apparatus wherein an individual layer can be removed so as to expose an unused layer thereby renewing the filter function of the filter apparatus.
Filter apparatus utilizing barrier-type filters have long been used for removing foreign materials and particulate from a contaminated fluid such as the intake air of an internal combustion engine. However, after a period of use, the function of the filter apparatus is substantially impaired to the point of being non-functional due to particulate and other foreign material being collected on the filter barrier surface. As a result, there have been developed several different methods for replacing a filter apparatus after its useful life has elapsed. For example, in some cases the entire filter apparatus is disposed of and a new one positioned in its place. In yet others, only the filter barrier media is exchanged. In still others, the filter media is washed for reuse. These approaches present problems in handling of the filter apparatus during the replacement process and/or are expensive to maintain as most if not all of the parts of a filter apparatus are disposed of.
The present invention solves these and many other problems associated with currently available filter apparatus.